The revolving door is generally located at an entrance of building structures to prevent the direct flow of air through a passage space when a user passes through the entrance. The revolving door is also used as a security door which restricts access into a room to authorized personnel.
Referring now to FIG. 1, there is shown a perspective view of a conventional revolving door assembly. The conventional revolving door assembly comprises a cylindrical vestibule including opposed curved side walls defining a passage space and passage openings, a central axis, and a plurality of door wings extending outwardly from the central axis. The door wings are partially enclosed between the opposed curved side walls and revolve together about the common central axis within the passage space.
According to the conventional revolving door assembly having the cylindrical vestibule, since the side walls are comprised of curved or arcuate members, the conventional revolving door assembly has several disadvantages. For example, the curved or arcuate wall is relatively difficult to manufacture so that materials to be used for the side walls are limited because of technical and/or economical reasons. According to the conventional revolving door assembly, the two spaced cylindrical walls are disposed to partially enclose the cylindrical passage space to define two diametrically opposed passage openings which are relatively narrow. To widen the width of the passage opening, larger side walls and larger door wings should be used and the revolving door assembly becomes bulky. Otherwise, the number of door wings should be increased to correspond with a wider passage opening but a compartment defined by adjacent door wings becomes too small. In addition, because of the cylindrical configuration, it is difficult to mount a shutter assembly which is used for a robbery prevention purpose at the revolving door assembly.
An object of the present invention is to provide a revolving door in which the opposed curved side walls are replaced by opposed vertical side walls having opposed substantially flat or plane surfaces.